In recent years, display devices that use light guide structures have been proposed. Such a display device includes, for example, multiple light sources in one column, multiple light guides connected respectively to the light sources, and light extraction units multiply provided on each of the light guide surfaces. An image can be displayed in the display device by physically or chemically changing the light extraction units to control an extraction and a non-extraction of light from the light guide surface by the light extraction units.
However, it is desirable to increase the light extraction efficiency in such a display device.